Spark plug



V 7 Z? I 25 27 q 6 5&1. 3 19 90 June 8, 1937. E. c. WAMELINK 2,083,283

SPARK PLUG Filed OCt. 2, 1935 EUGENE ELFVfiMELIA/K Patented June 8, 1937 UNITED STATES PATENT OFFICE SPARK PLUG elink, deceased Application October 2, 1935, Serial No. 43,242

Claims.

This invention relates to improvements in ignition devices for internal combustion engines generally known as spark plugs.

The primary object of the invention is to pro- 5 vide an ignition plug having a stationary electrode and an adjustable electrode whereby the ignition gap therebetween may be adjusted without necessitating the removal of the plug from the internal combustion engine.

A further object of this invention is to provide a spark plug of the above mentioned character including a central adjustable electrode mounted in a porcelain block or the like to which may be secured metallic sleeves by a spinning 1.) operation to insure against compression loss, re-

sulting when a loose connection occurs above the engine piston.

A still further object of this invention. is to provide a device of the above mentioned charac- 2O ter having means for determining the distance between the stationary electrode and the adjustable electrode without requiring the removal of the spark plug from the engine head or cylinder block.

. A still further object of this invention is to provide a spark plug of the above mentioned type having a graduated sleeve on the upper end of the insulator adapted to register with graduations formed on the locking nut to indicate the relative position of the electrodes.

A still further object of this invention is to provide a spark plug of the aforementioned character capable of being easily manufactured and presenting a compact unit for increasing the efficiency of engine operation.

Other objects and advantages of the invention will become apparent during the course of the following description taken with the drawing, wherein, Fig. 1 is a vertical cross sectional view of the spark plug embodying this invention.

Fig. 2 is a side elevational view illustrating the insulated adjustable electrode removed from the threaded metal plug.

Fig. 3 is a top elevational view of the graduated locking sleeve and thimble; and

Figure 4 is a vertical cross sectional view of a modified form of the invention.

In the drawing wherein for the purpose of illustrating the invention and wherein like reference characters will be employed to designate like parts throughout the same, the reference character 5 in Figures 1 to 3 inclusive will generally be employed to designate a spark plug shell having a wrench engaging portion 6 and a reduced screw threaded end 1 adapted to be received in the spark plug opening formed in the cylinder head of an internal combustion engine.

The upper end of the shell 5 is provided with an enlarged bore 8 screw threaded'as at 9 while the lower portion of the shell 5 is provided with a reduced bore it screw threaded as at H.

Formed on the extreme lower reduced end of the shell 5 is a stationary electrode 52 having its free end l3 presented to the center of the 10 shell in direct alinement with the adjustable electrode which will be hereinafter more fully described.

The adjustable electrode includes a vertical member M which may have its upper end is threaded and extends above the insulator iii a distance sufficient to receive a nut or other electrical contact member.

Enlarged portions l1, i8 and iii are formed on the insulator i6 defining reduced portions 25), i 2! and 22 respectively.

Surrounding the uppermost enlarged portion I1 is a metallic sleeve 23 having its upper and lower portions spun into close contact with insulator it as at 24 and 25. This construction insures against loss of compression and also forms a guide within the lock nut 26 having threads 21 received in the corresponding screw threads 9 formed in the shell 5.

Graduations 2'! are formed on the lock nut 26 as shown in Figure 3 and said graduations are adapted to register with legend marks 28 formed on the spun portion 24 of the sleeve 23 whereby the distance of the lower end of the electrode M from the stationary electrode it may be determined in fractions of an inch by manipulating the insulator l6 with respect to the shell 5.

A metallic sleeve 29 is spun upon the enlarged portion l9 of the insulator It as 3!! and 3! and the spun portion 3% is flared into o contact with the lower portion of the enlarged section I?! of the insulator to form an annular lip for engaging the lower portion of the locking nut, 26. A gasket 32 may be interposed between the lock nut 26 and outwardly flared portion 45 of the spun section 30.

It is to be understood that the sleeve 29 may be spun to cause the portion 30 to closely engage the reduced portion 2| of the insulator and likewise the spun portion 3| may be spun into close engagement with the reduced portion 22.

Screw threads 33 are formed on the sleeve 29 for being received in the screw threads l l whereby rotation of the insulator It will cause the 5 electrode M to be moved toward and away from the stationary electrode l2.

After the electrode M has been adjusted to the desired position to arrange the desired gap between the electrodes I3 and M the locking nut 26 may be tightened in place to prevent the escape of compression through the shell 5. Should the gap between the points l3 and !4 become out of adjustment it is merely necessary to loosen the nut 26 and turn the insulator l6 until the desired gap is produced as indicated by the graduations 21 and 28 on the nut 26 and sleeve 24 respectively.

In the modified form shown in Figure 4 the shell 5a is substantially identical to the form shown in Figure 1 and includes a reduced screw threaded portion Ia and is provided with an enlarged bore 8a, threaded in its upper end as at 9a. Said bore 8a has its lower portion reduced as at Illa and is internally screw threaded adjacent its reduced section as at Ila. Formed on the lower reduced portion 1a is a stationary electrode l2a having its free end l3a presented to the center of the reduced bore Illa, in close relation to the adjustable electrode Ma.

The electrode Ida is surrounded by an insulator l6a having an enlarged portion l'la bevelled as at IBa adjacent its upper end. An annular flange l9a is formed intermediate the ends of the insulator Ilia and the lower portion of the insulator is tapered for the rest of its length terminating in close proximity to the lower end of the electrode Ma.

Encircling the enlarged portion Ila of the insulator 5a is a metallic sleeve 23a having its upper end spun into close contact with the bevelled portion 18a of the insulator and extending upwardly for a shOrt distance of the upper end of the insulator as at 2411. The lower end of the sleeve 23a is flared outwardly to form a flange 25a abutting the annular flange lSa.

Embracing the outwardly flared flange 25a is a collar 26a which confines the annular shoulder l9a and is secured in position by being spun or pressed into close contact with the insulator.

Screw threads 21a are formed on the lower end of the collar 26a for being received in correspondingly shaped threads Ha formed in the reduced portion of the shell 5a.

A packing gland nut 30a is provided with. screw threads 3Ia for being received in the screw threads 9a formed internally in the upper end of the shell 5a whereby a tight connection between the gland nut and sleeve 23a may be maintained for preventing compression losses.

It is intended to provide the shell 23a with graduations or legends upon the bevelled portion engaging the bevelled step l8a of the insulator and also provide the gland nut 30a with indications similar to those at 21 shown in Figure 3. Obviously the graduations could be formed on the gland nut 30a and the indications placed on the upper end of the shell engaging the bevelled portion 3a of the insulator, with equally good results.

i It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred forms of the invention and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, what I claim is:

1. An ignition device of the character described comprising a shell, a stationary electrode secured to the lower end of the shell, an adjustable electrode mounted in the shell, an insulator having an enlarged shoulder, a threaded collar surrounding the shoulder threaded into the shell and means upon the upper end of the shell and insulator for indicating the distance between the stationary and adjustable electrodes.

2. An ignition device of the character described comprising a threaded shell adapted to be received in the engine head of an engine, an electrode carried by the lower end of the shell, an adjustable electrode having its lower end presented to the first mentioned electrode, arranged in shell, an insulator surrounding the adjustable electrode having an enlarged shoulder, a threaded collar confining the shoulder threaded in the shell, and indicating means carried by the electrode and shell, whereby the position of the electrodes may be determined without removing the shell from the engine head.

3. An ignition device of the character described including a shell having external and internal screw threads, an electrode secured to the lower end of the shell, an adjustable electrode mounted in the shell, an insulator surrounding the electrode, an enlarged shoulder formed on the insulator, a collar secured on the shoulder, a gland nut threaded in the upper end of the shell, a collar secured on the upper end of the insulator and graduations formed on the gland nut and second mentioned collar whereby a change of position between the electrodes may be deter mined from the upper end of the ignition device.

4. An ignition device of the character described including a screw threaded shell, an electrode se cured to the lower end of the shell, an adjustable electrode mounted within the shell, an insulator separating the electrode from the shell having an enlarged shoulder formed on the upper and lower ends of the insulator, collars surrounding the enlarged shoulders, threads formed on the lower collar for being received in the shell and a gland nut engaging the uppermost collar.

5. An ignition device of the character described including a screw threaded shell, an electrode secured to the lower end of the shell, an adjustable electrode mounted within the shell, an insulator separating the electrode from the shell having an enlarged shoulder formed on the upper and lower ends of the insulator, collars surrounding the enlarged shoulders, threads formed on the lower collar for being received in the shell, a gland nut engaging the uppermost collar, and means on the gland nut and upper collar for indicating the position of the electrodes.

EUGENE C. WAMELINK. 

